Rudder shaft packing material

[erps]

I was back underneath working on something else when I was looking at my rudder shaft tube. It looks like a plastic material with a screw on cap that the rudder shaft comes out of. I unscrewed the cap (above waterline) and noticed some sort of packing material in there. Pulled a piece out and didn't recognize it, so pushed a little grease in there and put the cap on.

My question is, one of these days I suppose something is going to wear out in there. I didn't see any grease fittings on the tube. Anyone know what kind material/maintenance one should do on the rudder shaft?

[Rockter]

It's normally above the water line, and so sealing is not vital. If it leaks, then give it some attention.
If it is above the water line, it is not going to leak much as only surge in the tube will need defending.

[danielgoldberg]

It's just like your prop shaft stuffing box, most likely. Rudder shafts have stuffing boxes or shaft seals just like prop shafts. Obviously the rudder shaft doesn't turn as much, so doesn't heat up the same way, but it's packing material in there I bet. You are correct that eventually the stuffing box will need to be repacked. When you start getting water coming into your bilge from somewhere aft, and it only happens when you're heeling, or motoring, or something like that where it's intermittant and driving you nuts because you can't find the source, check that rudder bearing stuffing box.

[gc1111]

My rudder shaft packing fitting looks exactly like the prop shaft packing fitting (Allied Mistress 39). It is repacked in exactly the same manner. Only I have only repacked it once in 15 years. It takes a different size packing which is the only difference other than the amount of wear due to the difference in rotation.